December 31, 2018

The ‘Y’ Classification of Zirconia

Paul Cascone, BE MetE, MS, Senior Vice President, Research and Development

Have your dentists asked you how much yttria there is in your zirconia? Typically, this question comes after the dentist has been to a lecture or heard other clinicians refer to “3Y” or “5Y” zirconia.

This classification system is called the "mole percent" of yttria present in the zirconia. Most companies provide a weight percent of zirconia rather than mole percent.

The table below shows the comparison between the two systems as well as some examples of zirconia brands that fall within each category.

Weight Percent Yttria   Mole Percent Yttria        Example Zirconia
5.5 weight percent  3 mole percent (3Y)  ArgenZ Ultra, ArgenZ Esthetic, BruxZir, NexxZr
6.9 weight percent  4 mole percent (4Y)  ArgenZ HT+ 
9.3 weight percent  5 mole percent (5Y)  ArgenZ Anterior, BruxZir Anterior 


To learn more about how to calculate mole percent please refer to this link:

To order ArgenZ Zirconia products, click here